Good data will also help you understand what your members' usage mix is right now between PIN and signature debit. This is important, because the big bank cap on interchange, which is irrespective of authorization method, will cause more transactions to be processed as PIN transactions over time. If this comes to pass, consumer behavior may be permanently changed, creating additional downward pressure on interchange. As your margins decrease in the long run, it is going to be even more critical for you to carefully manage that PIN and signature mix.

Of course, you want to give your members every means of accessing their accounts possible, but you need to be aware of what the margins are on the different types of transactions. That's where good data mining comes into play, and this will pay off in well-informed decisions as you execute your marketing game plan.

Stress the credit union difference. Credit unions came into existence to improve the financial lives of their members, many of whom have historically been people of modest means. Better rates on loans, fewer fees and more personalized services have been, and will continue to be, a differentiator for credit unions. There has never been a better time to market this fact to potential new members and to inactive existing members.

Stress acceptance of credit union-issued credit and debit cards. With the many landmark and complex changes in the regulation of financial institutions, there may be some uncertainty among your members as to whether or not their credit union-issued cards will be accepted at the point of sale. In fact, the banks may imply this in their marketing programs. Credit unions should be educating members, letting them know that their cards will be accepted by merchants just as before, and that this is written into the Federal Reserve Board's rules.

Take advantage of the two other exemptions. In addition to financial institutions with less than $10 billion in total assets, there are two other “exempt parties” that credit unions can participate in to maximize their marketing advantage. The two additional exemptions may be opportunities for you – debit cards provided under government payment programs known as electronic benefit transfer, and reloadable prepaid cards redeemable at multiple, unaffiliated merchants. Both of these products further expand a credit union's efforts to serve underserved consumers who might get left behind by the big banks.

Grow your checking account base. Checking accounts are the surest way to convert inactive members into members who look to you as their primary financial institution. Free checking is alive and well at credit unions, while banks have killed it off. Here is a real opportunity for credit unions in midst of a crisis for big banks.

To jump start this growth, consider implementing rewards checking accounts and offering the richest benefits to members who meet your criteria for direct deposit, online bill payment, receiving electronic statements instead of paper statements and check card or debit card activity.

You haven't lost any interchange income yet, By marketing the credit union difference today, protect your profitability for the future. 

Caroline Lane is senior vice president of business development and marketing at CO-OP Financial Services.